Generator assembly apparatus for uniform pressure absorption type refrigerators



Dec. 30, 1952 w. L. EDEL 2,523,366

GENERATOR ASSEMBLY APPARATUS FOR UNIFORM PRESSURE ABSORPTION TYPE REFRIGERATORS Filed June l5, 1949 3 Sheets-Sheet l WAL TER 1 spez.

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Gttorneg Dec. 30, 1952 w. 1 EDEL 2,523,355

GENERATOR ASSEMBLY APPARATUS FOR UNIFORM l PRESSURE ABSORPTION TYPE REFRIGERATRS Filed June l5, 1949 3 Sheets-Sheet 2 IIIIIIHIIIH IHIIIIIIHI lllllllllllll :inventor WAL Ts@ I.. 50E/ Gttomeg Dec. 30, 1952 w. 1 EDEL 2,623G65 GENERATOR ASSEMBLY APPARATUS FOR UNIFORM PRESSURE ABSORPTION TYPE REFRIGERATORS 5 Sheets-Sheet 5 Filed June 15, 1949 m (ww lwentor WALTER L. EDEL attorney Patented Dec. 30, 1952 GENERATOR ASSEMBLY APPARATUS FOR UNIFORM PRESSURE ABSORPTION TYPE REFRIGERATORS Walter L. Edel, Louisville, Ky., assignor to Clayton & Lambert Manufacturing Company, Louisville, Ky., a corporation of Delaware Application June 13, 1949, Serial No. 98,722

23 Claims. l

This invention relates to improvements in uniform pressure absorption type of refrigerating apparatus and has particular reference to the generator assembly for generating vapor and circulating liquor to and from the absorber. This application is a continuation in part of my application, Serial No. 744,202, filed April 26, 1947.

One important object of the invention is to provide a novel generator assembly of simple and inexpensive form having a highly eflicient heat transfer characteristic.

Another important object is to provide such an assembly with a lift arrangement which utilizes the generated vapor to lift the strong liquor upwardly into a separator and which is so arranged as to insure the proper ilow relationship between the generated vapor and the lifted strong liquor.

Another important object is to provide a novel generator assembly which utilizes vapor pressure to supplement the liquid head normally provided to effect a circulation of liquor back to the absorber inlet.

Another important object is to provide, in the generator-absorber liquor circulating system, a

novel generator arrangement which enables the over-all elevation of the generator assembly to be reduced to a substantial degree, which may be so utilized as to permit a reduction in the overall elevation of the absorber assembly, and which insures an effective return flow of liquor to the absorber assembly.

Another important object is to provide a generator assembly which, when properly charged with liquid and gas and then inverted, will automatically recharge itself 4for proper operation when restored to an upright position.

The invention is illustrated in the drawings wherein:

Figure 1 is a cross-sectional view of reduced scale taken along line I-l of Figure 2;

Figure 2 is a more or less schematic view of a vertical section through a circulating system having a generator assembly constructed in accordance with this invention;

Figure 3 is a schematic view showing the layout of another embodiment constructed in ac cordance with this invention; Y

Figure 4 is a view, similar to that of Figure 3, showing a slightly diierent embodiment of the invention; and

Figures 5, 6 and 7 are schematic views based on Figures 3 and 4 respectively, Figure 5 showing the height of the generator assembly of Figure 3 when vapor pressure is not used in effecting a return ilow of liquor to the absorber,l Figure 6 showing the reduction in the height of the same! generator assembly when vapor pressure is used" to supplement the liquid head favoring thereturn flow of liquor to the absorber, and Figure 7:. showing the greater reduction of height of the' generator assembly and a reduction in the height of the absorber assembly, obtained with the higher supplementary vapor pressure design of Figure 4. Y

The generator assemblies illustrated in Figures an outlet section 5 which discharges into :a re

ceiver 6 provided with a chargingplug 1 at its charging level and a strong liquor discharge conduit 8.

Generator assembly structure of Figure 2 This generator assembly comprises: an outer and preferably L-shaped shell l0; an inner shell. Il of similar L-shape which is spaced inwardly. fromthe outer shell and arranged to provide an i. inner chamberwithin the inner shell, and an f, outer chamber l2 between the outer and inner` shells l0 and Il, this outer chamber I2 being in` open communication with the inner chamber atA the hot end or toe of the assembly, and being' closed at its upper end where the two shells l0, and H meet; a shell extension I3 continuing one of the shells upwardly beyond the upper end of the outer chamber andproviding an upward @Lxtension of the inner chamber which leads to the refrigerant condenser (not shown); insulation It covering the outer shell ID and the shell4 extension I3; a vent connection i5 leading upwardly through the inner chamber from the upper end of the outer chamber, this connection venting, to

the condenser, any gases or entrained vapor thatI may accumulate in the outer chamber; and a heat exchange connection spaced slightly below the horizontal plane of the lower end of the vent con-` nection I5, this heat exchange connection comprising an outgoing weak liquor conduit i6 connected to the outer chamber and in heat exchange relationship with an incoming strong liquor conduit l1 connected to the inner chamber.

The vertical leg of the inner chamber contains,

between its lower end and the heat exchange connection, four partitions as follows: a horizontal bottom partition I8 which extends from the heel of the inner chamber transversely across part of the cross-sectional area of the innerchamber; a Vvertical partition I9 which extends' from the inner edge of the lower partition I8 upwardly and transversely across the inner chamber to a point just below the heat exchange connection; an upper horizontal partition 2u which extends from the upper end of the vertical partition i9 transversely across the remaining cross-sectionalarea of the inner chamber; and a horizontal partition 2| corresponding to but spaced somewhat below the upper partition 29. These partitions divide the inner shell into: a strong liquor compartment 22 lying above the bottom partition I8 and communicating with the incoming strong liquor conduit ll; a submerged separator 23 lying between partitions 2li and 2l and having an operating liquider separatorlevel with a closed vapor space above that level;f-'and a submerged generator having .a verticalstandpipe 24 extending downwardly irorn'the partition 2| through the foot of the inner shell, The generator:.;is normally nlled vwith liquid upto an -operatingliquidor :generator level 'in the standpipe 245andlhas Aa closed vapor space 'over `that level and-Lunder'partition 2l. The generator may be heated in 'any suitable 4way and it is shown as havingY a burner B atits toe end and a combustion" ilue F extending through the'base section 2'5an'd1then" turning upwardly to passsuccessive- 1y through partition I3 and compartment'ZZ.

vAfstrongY liquor lifting conduits extends from the 4.lowerr end 'portion tof 'compartment 22 upwar'dlyto'conne'ct intothe separator vapor space. This conduit'h'as a'vapor inlet Vorifice 2l, which should .be located cna :level approximately 1 or more'fabove the lowest point to which the vapor entering the orifice rmust travelito'rever'se its normal'iupward -direction of flow. A lower oriiice may -permit'the vapor to reverse andlow downwardly into compartment 22. The generator as'- sembly-structure-.iscompleted by conduit means which comprise: a conduit 28 for feeding generated 'vapor under pressure downwardly from thejgeneratorvapor 'space into the'lifting orifice 2'Ito'liftstrongliquorthrough the lifting conduit 26into fthe. separator'vapor space; `a conduit 29 for conducting a 'solid column of down-flowing strongliquor `from `the separator and discharging it into .the generator at a level below the generator level; and afconduit 3G for conducting separatedvapor underpressure from'the separator vaporrspace downwardly through compartment 22 toa discharge pointat a level between the separatorlevel 'and the lift orifice 2l, where it discharges ,into compartment 2 2.

.Liquid 'flow iof Figure .-2

.".Theliquor Acirculates'in Figure 2 downwardly throughthe absorber il, receiver 6 `and conduit 8, upwardly through theheat exchanger conduit il', downwardly through compartment "22, upwardly through 'lift conduit 2G, `downwardly through the separator 23 and generator sections 2&1 and 25,`

ahigh .level circuit beginning with a downlowl columnV in the high circuit separator 23 and ending with an uplow column forming the absorber inlet I. The liquor overiiows at 'level I to run l`downward fgravitationally through the absorberassembly :from the high circuit to the low and a horizontal base 25 extending Y 4 circuit. In the generator assembly, the liquor must be lifted from a low level in the low circuit to a high level in the high circuit.

The high level of Figure 2 nThe .high level required to effect van uniorced gravitational flow through the highcircuit is indicated in Figure 2 by the legend High Level. This high level must be slightly higher than the vent level V, in order that the weight of the .lighter strong liquorv forming the high circuit dowriiiow `column -may overcome the weight of the lheavier column of weak liquor forming the vent level Vvand thus cause the liquor to iiow :from Ythe Yhigh level to the vent level which, in -turn, .must .beuslightly higher than the absorber level I in order to overcome the otv resistance "of the' heat exchanger between levels V and I.

The lift height of Figure 2 .The vertical distance between the low level A andthe high leveliis herein called the liit height.

In Figure 2 we .assume that the high levelstan'ds 31/2" above the l'owlevel; hence'the lift height is 3%. It will'nowbe obvious that liquor must be pumped from the low level A into the high circuit separator tobuild the level of the downflow column 'upto a .point where the 31/2 lift height is created between 'such levels. vWhen'this is done the'high circuit iiovv" will'beinstituted at a rate corresponding to the '.ratev at which liquid is pumped from the low vcircuit to the high circuit.

The depressed levels In accordance with my invention, the high level or" the high circuitis depressed to a low separator level and low level liquid of the low circuit is equally depressed .to a lift level by building up a vapor Vpressure `or vaporrheadlinth'e high circuit `separator vapor space. Since both liquid-sf are depressed to the same extent by the same vapor pressure, the lift heightremains y1inchanged; hence the depressed low vcircuitliqu'id must .be .liftedrinto the high circuit. separator ZS until the .depressed separator level stands the'lift 'height above the Vlift level Voi? the depressed low level lliquid bef-ore a flow through the high oircuit will loe-instituted. Furthermore since the kvapor pressure inrhigh circuit equals the hydrostatic pressure-of the liquid it displaces, the-hydrostatic pressure of the depressed-Ad-ownow columnnecessarily remains'the same .as the hydrostaticpressure` of a non-depressed downow col- Separator vapor pressure YThe Vseparator vapor pressure can be built up by appropriately restricting the iiow of separated vapor from the 'separator into the vapor space of the shell extension I3. .It is conveniently and advantageously effected by discharging the vapor leaving the separator into the liquid of compartment v22 at a desired point below the low level A.

In Figure 2 we assume that the high level is depressed 'l1/2 to the separator level. Accordingly,

the separator is made t-o discharge its vaporA against the 'l1/2" hydrostatic head of the lowrlevel liquid; hence it must build up a vapor pressure `equal to such head before the vapor discharge can begin. In eiect, I have superposed'71/2 of hydrostatic head Vfrom the low circuit compartment 22 liquid onto the high circuit separator liquid through the'agenoy of a vapor connection between them.

The lift mechanism Since the assumed separator level stands '7l/2 below the high level, the lift level, formed by the depressed low level liquid, will also stand 'l 1/2" below the low level A. In other words the lift level in lift tube 26 stands at the same elevation `as the vapor inlet of compartment 22 where the vapor leaves conduit 36 to enter compartment '22.

The liquid is lift-ed from the lift level through the lift conduit into the separator vapor space by directing vapor from the generator vapor space into the lift conduit at an orifice level vsufficiently below the lift level to allow the generator level to stand the lift height distance above the orifice level. The generator level can therefore be made to stand at any selected elevation so long as the' orifice 21 can be located the lift height distance below it. However, the generator level must be below the generator vapor outlet and above its strong liqu'orinlet. Accordingly the orifice 21 is preferably located at an Ielevati-on such as to cause the generator level to stand about 3A below the generator vapor outlet.

With this assumed 31/2" arrangement, the generator will build up a vapor pressure equal to the hydrostatic pressure created by the hydrostatic head between the orifice and the low level A. This head equals in Figure 2. When this pressure is reached, generated vapor will enter the lifting conduit and lift liquor through that conduit into the separator.

Lift conduit flow ratio R Theoretically the securernent of the best operating results requires the lifting of a definite amount of strong liquor by all of the vapor generated from an equal amount of liquor. In other words, there is a proper flow relationship between the amount of strong liquor lifted and the amount of vapor generated and this relationship should be established to obtain the best operating results under all conditions of operation.

I have found that this ow relationship varies with the ratio of the distance between the orice '21 and the lift level to the distance between the lift level and the level at which the lifted liquid is raised before it enters the separat-or. My `experience indicates that, with the lifting conduit of substantially uniform bore, this ratio, which is herein called rati-o R, should not go substantially above .80 or substantially below .60 and that good results may be uniformly expected when ratio R approximates .70.

In accordance with my invention the flow ratio R is incorporated in the lift conduit and, in Figure 2, this ratio approximates .60 to .625,

`Charging and operating Figure 2 It will be appreciated that when the absorber and generator assemblies are exhausted and then charged with strong liquor followed by a charge of hydrogen gas, the liquor will flow into and ll compartment 22 and outer chamber I2 up to a level approximating level A, and, at the same time, completely fill the generator, separator and conduits 26, 28 and 30. When heat is applied vapor will be generated in generator 24 and as the pressure builds up the liquid will be forced downwardly through conduit 2-8 until the vapor pressure at the orifice 2l equals the hydrostatic head of the liquid between orifice 2l and level A. At this time vapor will pass upwardly through conduit 26 into separator 23. i

As the pressure` builds up inseparator 23, it

forces the liquid level in tubes 2B and 30 down` wardly until it reaches the lower end of tube 30 when the separator vapor pressure will equal the 'l1/2" hydrostatic head of the liquid between 5i the lower end of conduit 30 and level A. If the appropriate generator, separator and vent levels have not been reached at -this time, the system will continue lifting liquid into the separator to build up levels until the separator reaches the normal operating or separator level which, in conjunction with the separator vapor pressure already established, is required to force liquor up to the vent level and to thus initiate the flow to the absorber.

It will .be appreciated that the arrangement of Figure 2 is highly efficient in operation from a heat transfer standpoint. Elicient operation is secured in the generator assembly because: the generator and separator are submerged; the flue F, compartment 22, separator 23 and generator 24 and all contained within the inner shell and surrounded by the weak liquor chamber I2; the generated vapors are taken off at the cold end of the generator; and the weak and strong liquors are in good heat exchange relationship in `the heat exchanger. Furthermore, by using the generated vapor to raise the strong liquor, I obtain a further transfer of heat resulting in an increase in the temperature of the strong liquor going to the generator and a decrease in the useless super-heat of the generated vapors, this later decrease being accomplished by a condensation of some of its water Vapor content. A similar heat transfer is obtained when the separated vapors flow from conduit 30 upwardly through compartment 22, this portion of compartment 22 functioning as an analyzer.

Corresponding elements of Figures Z, 3 and, 4

The generator assemblies of Figures 2, 3 and l contain corresponding elements which, in Figures 3 and 4, comprise: a separator 50 arranged to receive and separate strong liquor and generated vapor, said separator having a strong liquor operating or separator level and a closed vapor space over said separator level for accumulating sep-arated vapors under pressure; an analyzer 54 arranged to receive and discharge a stream of `strong liquor and to analyze separated vapor in said strong liquor from a vapor inlet 55 at a level substantially below the separator level elevation upwardly to an analyzed vapor outlet level A; a strong liquor lifting conduit extending upwardly and connecting into the separator vapor space, said lifting conduit having a strong liquor operating or lift-level at the level of the analyzer vapor inlet 55 and a lifting vapor inlet orifice 6I below said lift-level; a generator 63 having an operating liquid or generator level at an elevation above that of said lifting orifice 6l and below that of said separator level, a closed vapor space over said generator level for accumulating generated vapor under pressure and a weak liquor outlet 64; and conduit means including conduit 58 for conducting strong liquor from analyzer into the lifting conduit 60 where it flows up to the lift-level, conduit 61 for feeding generated Vapor under pressure downwardly from the generator vapor space into the lifting orifice 6I` to lift the strong liquor through said lifting conduit 60 into the said separator vapor space, conduit 52 for conducting a solid column of down-flowing strong liquor from the separator 50 and discharging it into the generator 63 at a level below the generator level and conduit 53 i for vconducting separated vapor 'under pressure from the vseparator vapor space to the analyzer vapor inlet 55 through which it flows to pass upwardly through the strong liquor to said vapor outlet.

Structure of Figures 3 and 4 The separator 5e comprises a shell 5o having a 'strong liquor operating or separator level, a closed vapor space over that level, an inlet opening 5! for receiving strong liquor and generated vapor, a strong liquor discharge conduit 52 depending from its bottom and a vapor discharge conduit 53 for `conducting the separated vapor from the closed vapor space to the analyzer 5d.

The analyzer 5d is in the form of an inclined tube 5d providing a path for the ilow of vapor from a vapor inlet 55 upwardly to an analyzed vapor outlet llevel A at which the analyzed vapor leaves the liquor circuit to enter a vapor feed conduit 5S leading to the refrigerant condenser not shown. The strong liquor for analyzing this vapor enters the upper end or" the analyzer through a strong liquor inlet 5l, flows downwardly through the analyzer tube 5ft in countercurrent relationship to the vapor, and leaves the lower end of the analyzer to pass through an outlet liquor conduit 58 which connects with the lower end of the lifting conduit 65.

The lifting conduit 65 is in the form of a vertical tube Si! extending upwardly from its lower end connection to conduit 5S, with its upper end connected to the inlet opening 5I of separator 5i. This conduit has a strong liquor operating or liftlevel at the level of the analyzer vapor inlet 55 and a lifting vapor inlet orifice 5l below this lifting level but suhciently above the lower end of the lifting tube 55 to prevent vapors entering the orice 5l from passing downwardly to i'iow through conduit 58.

TheY generator 53 comprises a horizontal shell 53 having a. combustion tube 62 passing centrally therethrough, a weak liquor outlet tube 64 at one end and a standpipe 55 at its other end. The weak liquor outlet tube 5d extends from the generator centrally through the analyzer tube 56. The generator is so arranged that all vapor generated in it travels toward and collects in standpipe 65 which has an operating liquid or generator level at an elevation above that of the lift orifice iii and below that of the separator level, a closed vapor space over the generator level, a generated vapor outlet opening 35 and a. vapor discharge conduit 5l leading from the generator vapor outlet E55 downwardly to discharge through the orifice 5l into the lifting conduit Sii. Preferably, the separator shell Eil and the standpipe 65 are made as one integral shell with a partition E8 dividing that shell into the upper separator chamber and lower standpipe or generator chamber, this partition. supporting the strong liquor discharge conduit 52 which depends downwardly into the standpipe to an elevation well below that of the normal generator level.

The heat exchanger, which connects the generator and absorber assemblies together, com.- prises an outer strong liquor tube 'iii extending upwardly from the discharge conduit S of the receiver 6 to the strong liquor inlet 5i of the analyze-r 5d and connected to both; and a weak liquor tube li extending centrally downward through the 'strong liquor tube 'it Wi th its upper end connected through vent connector 'i2 to the upper end of the weak liquor generator outlet tube 6, and'with its lower end vconnected to weak liquor conduit i leading tothe absorber. The vent connector projects upwardly fromits 'connection with tube 6e beyond the weak liquor ve-nt level and communicates through vapor conduit 'I3 with the vapor conduit 53 between the separator and analyzer.

Opera-tion of Figures 3 and 4 The operations of the arrangements shown in Figures 3 and 4 are identical with each other. They are substantially the same as that of Figure 2, the only diiierence being that the vent conduit of Figures 3 and 4 is connected to the separator chamber discharge conduit 'i3 placing the vent level under the separated vapor pressure whereas the vent level in Figure 2 is not under pressure.

In Figures 3 and 4 strong liquor flows'from re'- ceiver level R through conduit 8, the outer heat exchange conduit lil, the analyzer54, which establishes the lower level A, and conduit 58 into the lift conduit t5. At the same time, generated vapor under pressure comes from the vapor space of the generator standpipe 55 through its vdischarge opening 66 and discharge Vconduit f6l to enter the lifting conduit t5 through oriiice 6I. The lifted liquid enters the separator Where the vapor and liquid separate. The separated vapor builds up pressure until it overcomes the hydrostatic head at the analyzer vapor `inlet whereupon it passes upwardly through the analyzer in countercurrent relationship to the down'- iowing strong liquor and discharges fromthe analyzer level A toy pass into conduit 56 which conducts it into the condenser not shown.

rShe separated strong liquor in 'separator 50 passes. through downpipe 52, generator 63, weak liquor tube @il to enter vent connector 'I2 from which it flows through weak liquor tube 1| of the heat exchanger and conduit l back to the inlet section 3 of absorber 4.

Any entrained vapor in the weak liquor iiowing to or from the vent connector 'i2 and any noncondensible gases in such weak liquor pass upwardly through the Vent connector 'I2 discharging into conduit i3 and passing to conduit 53 where it joins the separated vapor entering the analyzer.

In ord-er to bring out the features incorporated in Figures 3 and 4, reference will now be made to the schematic views of Figures 5, 6 and '7. All elevations are stated herein with reference to the same zero reference line.

Figure 5 Figure 5 is a schematic view basedvon Figure 3 except that vapor .pressure is not built up in the separator, the vapor and gases from the separator and vent connector being surface analyzed in the analyzer before going to the condenser. In Figure 5, we assume: a` 5% receiver Vlevel R; a '[low resistance drop of 1/4 from the receiver through the heat exchanger to a low level in the analyzer of 61/2" and a negligible drop from the analyzer through conduit 58 to a lift level in conduit 55 of 6%.

With a 17/3 drop in the absorber between level I and the 6%" level R, the level I is established at 8%. ln order to make liquor iiow from the vent connector through the heatexchanger to an absorber level I of 8%, with a-'low resistance drop in the heat exchanger of l/r, the vent level must be 87/8 and, to provide an excess` head of as a safety feature, the required vent level becomes 9%. The difference in density between the lighter strong liquor flowing from the separator andthe heavier weak liquor flowing into the vent connector requires the separator level to be 1A higher than the vent level thus establishing the separato-r level at Under the conditions assumed, the 1'0" separator level is not depressed and, therefore, stands at the same elevation as the high level while a lift height of 31/2 is established between the low level A and the high level.

To lift low level liquid to the high level separator, vapor is generated under pressure and introduced into the orifice 6I. The lowest safe elevation of the orifice is approximately 1" above the lowest point to which such vapor must flow before it can reverse its normal direction of travel. Since such lowest point is on the zero reference line for these elevations, the orifice vcan be and is placed at an elevation of 1".

The hydrostatic pressure at the orice level is 51/"; hence the vapor pressure of the generator is equivalent to this 51/2" hydrostatic pressure. This automatically places the generator level 51/2 below the high separator level or at an elevation of 4.1/2 above the reference line. The generator vapor outlet 66 should be placed at least 3A above the generator level in order to avoid any possibility of generated liquid being carried into the lifting conduit.

With 51/2 of generator pressure, liquid is lifted into the separator and the separator level will rise until equilibrium flow conditions are established. It may be that equilibrium flow conditions will be established in actual operation before any part of the excess head is utilized or when only a portion of it is required. In such event, the separator level will not rise to the 10" level but, on the contrary, may stop at some value such, for example, as 91/2". In such case, the actual lift height will be 3" instead of the assumed 31/2. The generator level will move to the 4" elevation because a rise or fall in the separator level will be accompanied by a corresponding and equal rise or fall in the generator level, the 51/2" generator vapor pressure remaining unchanged. For the sake of clarity, we shall hereinafter assume that the lift height actually required remains at 31/".

With the orice 51/2 below the 6% lift level, the establishment of proper flow relationship, from llow ratio R, requires the lift conduit El) to extend upwardly from the lift-level a distance approximating 7%. This places the inlet 5l of the separator at an elevation approximating 14% so that the total elevation of the separator necessarily approximates 141/2 to 15".

As indicated in Figure 5, the generator-separator shell projects substantially above the remainder of the generator assembly. Where the generator is placed below the food compartment, it is desirable to reduce the overall height of the generator assembly because it enables the food compartment of a refrigerating unit of given height tc be correspondingly enlarged vertically or alternatively permits the overall height of an equivalent refrigerating unit to be correspondingly reduced.

To effect a reduction in the height of the generator assembly, I take advantage of the fact that a back pressure can be built up in the separator to drop the actual liquid level while maintaining the same hydrostatic pressure. This is illustrated by Figure 6.

Figure 6 In Figure 5 the separated vapor does not act against `any liquid head in the analyzer. In

Figure 6 the separated vapor is made to act `against a hydrostatic head in the analyzer to build up a corresponding vapor pressure in the separator. Accordingly, the vapor inlet of-the analyzer is dropped l below the 6% low level A of the analyzer so that the separated vapor must build up a vapor pressure equa-l to this 1" column of liquor in the analyzer before vapor can discharge through the analyzer. With this change: the I and R levels of the absorber assembly and the high, low, generator and orifice levels of the generator assembly all remain unchanged, whereas the separator, vent and lift levels of the generator assembly are all depressed 1 by the pressure of the separated vapor.

Since the lift level of the generator assembly has been depressed 1", the length of the lifting conduit from the lift level to the separator should be and is reduced, in accordance with iiow ratio R, approximately to 61/2. Accordingly, the lifting conduit extends, from the reference line, upwardly l to the orifice level, 4% more to the lift level and 61/2 more to the 12" level where it discharges into the separator. This makes it possible to reduce the height of the generator assembly to an elevation which is slightly above 12, say 121/2. Thus the assembly of Figure 6, with 1" separated vapor pressure, is approximately 2%" shorter than that of Figure 5. i

In Figure 6 the vapor inlet of the analyzer was lowered for vapor pressure purposes but located slightly above the generator vapor outlet 66 for charging and recharging purposes as will be explainedhereinafter. The fact that the analyzer vapor inlet of Figure 6 is positioned above the generator vapor outlet 66 limits the amount of vapor pressure which can be developed in the Figure 6 arrangement while maintaining the same reduced height unless some other means of restricting the flow of separated vapor is provided. Without such other means, the only way of increasing the separated vapor pressure of Figure 6 is to lower the analyzer inlet still further. This is essentially what is done in Figure 7.

VR, in the low circuit, the absorber level I in the high circuit, and the high, separator and vent levels in the high circuit, all to be lowered 1". The lowering of these levels enables the height of the generator assembly to be correspondingly reduced but it does not have any effect on the separator vapor pressure.

To provide a separator vapor pressure of greater magnitude in Figure 7 than is obtained in Figure 6, the analyzer vapor inlet must be lowered more than 1. As shown, it is lowered 1%" below the low level A; hence the separator, 'vent and lift levels are now depressed H by the separator vapor pressure. The lowered analyzer inlet stands at. an elevationof. which brings the liftglevel downy tothe same' elevation. With this reduction,

the length of the lifting conduit from the liftlevel'to its discharge level is reduced to 4 more or .less permitting the lifting conduit to kconnect intothe separator at an elevation of ,7lso that the overall height of the generator assembly approximates 8f which is 7v and 41/2" shorter than the assemblies of Figures and 6 respectively.

Recharcmg feature of Figures 3 and 4 The refrigerating apparatus illustrated in this application is assumed to be, and is explained as, one utilizing ammonia, hydrogen and Water `system` although any other suitable system may be employed. Each of the circulating systemsiof Figures .3 and 4 may be and preferably is `charged by ,first exhausting the system, next introducing therammonia .solution or strong lquorinto the receiver andfinally introducing the hydrogen gas. As the strong liquor is introduced into the receiver, it passes t-hrough the low circuit into 'lift tube 50 where it also floods through orifice 6i rising upwardly through both conduits 6U andBl.

When the level in these yconduits reaches the level of standpipe opening 66, the liquid vwill overflow into the standpipe and begin to build .upa level in the horizontal section of generator 63. Ammonia will begin to evaporate from the liquid in generator 53 and the gases thus formed will escape through conduit 64 back to the-absorber Yuntil the .generator connection to conduit d is sealed by liquid and through conduit 52, either to conduit 56 .through theanalyzer 54 or back to the absorber through `conduit -13 until the lower end of the downpipe Y52 is sealed off by liquid.

By the time the lower endof downpipe 52 is sealed off by liquid, the generator has suicient liquid in itto seal oir" any entrance by hydrogen. As a result the hydrogen pressure will compress the vapor inthe generator proper causing it to condense into the solution and thereby permit the liquid level in the generator to rise. lHow-- ever, once vthe lower end of downpipe 52 is sealed off, the operation of the unit can be instituted simply by applyingrh'eat at the combustion jtube.

Upon inverting the unit, the liquid in the absorber assembly will flow tothe evaporator which is not shown while that in the analyzer will flow to the condenser which is not shown. However, the liquids in the generator and separator Aare trapped since these liquids Vmust, when the absorption type refrigerating apparatus of the character wherein liquor flows through a'low circuit from an absorber assembly to a low vlevel in a generator assembly where itis lifted to flow through a high circuit from a downflow column in the generator assembly to a 'delivery level in the absorber assembly comprising: a low circuit analyzer for holding strong liquor up to the nor# mal low or analyzer level of the low circuit, said analyzer having a vapor outlet above and aV vapor inlet substantially below said level and strong liquor inlet and outlet openings positioned to accommodate a downflow through the vanalyzer of strong liquor rreceived from the absorber assembly;` a vertically 'arranged lifting conduit having its lower end connected to receive strong liquor from-the analyzer strong liquor outlet up to a lift level which is depressed below said analyzer level, said lifting conduit having a vapor inlet oriiice below its lift level; a high circuit separator for holdingstrong liquor of said high circuit downflow column up to a depressed separator level, said separator having, over its level, a closed vapor space connected to the upper end of the lifting conduit to receive strong liquor and vapor there,- from and a vapor outlet for that space, and, be,- low its level, a strong liquor outlet; a high circuit generator for holding liquid up to a depressed generator level which is above the lifting conduit orifice and below the analyzer level, said generator having, over its level, a closed vapor space and a vapor outlet for that space; a `downiow vapor conduit directing vapor under pressure from the generator vapor outlet downwardly and discharging it into the lift conduit oriiiceagainst the pressure head at that orifice; a downlow vapor conduit directing vapor under pressure from the separator vapor outlet downwardly and discharging it into the analyzer vapor inlet against the pressure head at that inlet; and a downflow liquor conduit connecting the separator strong liquor outlet to the generator below the depressed generator level.

2. The assembly of claim 1 wherein the analyzer low level is below the separator level and above the level of the generator vapor outlet.

3. The assembly of claim 2 wherein the analyzer vapor inlet is below the separator level and above the level of the generator vapor outlet.

4. The assembly of claim 1 wherein the analyzer low level is above the level of the generator vapor outlet and the analyzer vapor inlet is below the level of the generator vapor outlet but above the level of the orifice.

5. The assembly of claim 2= wherein the analyzer low level is on a horizontal plane adjacent the topside of the generator vapor outlet.

6. The assembly of claim 1 wherein the bore'of the lifting conduit is substantialy uniform from the orifice to the horizontal level at which it discharges into the separator and the ratio of the distance between the orice and the lift level to the distance between the lift level and said horizontal discharge level is not substantially above .80 or substantially below .6,0.

7. An improvement in a generator assembly for uniform rpressure absorption type refrigerating apparatus of thecharacter wherein one continuous stream of liquid iiows through a high circuit from a generator assembly downfiow column to theinlet of the absorber assembly and another continuous stream of liquid ows through'a low circuit from the absorber assembly outlet to a low level in the generator assembly-comprising: a high circuit separator containing relatively cool strong liquor forming the upper end of said high circuit downflow column which extends up `toa vapor depressed separator level and which has the high pressure head required for circulation purposes, said separator having a closed vapor space over said level; a high circuit generator arranged ,in series with said separator to receive strong 13 from the low level liquid in the low circuit upwardly into the high circuit separator, said `means including a lift tube and a vapor pressure tube, said lift tube being arranged to receive strong liquor up to a vapor depressed liftlevel and to conduct it into said separator, said lift tube having a vapor inlet orifice substantially be loW the lift and generator levels, said vapor pressure tube being arranged to receive vapor under pressure from the generator Vapor space, conduct it downwardly and deliver it into said lift tube orince against the pressure head existing at the orifice; a low circuit analyzer for holding strong liquor from the absorber up to the normal or low analyzer level of the low circuit, said analyzer accommodating a downiiow of strong liquor from an inlet which receives it from the absorber assembly to an outlet which delivers it to the lifting means, said analyzer having a vapor outlet above its low level and a vapor inlet substantially below said low level; and means directing the vapor from the high circuit separator vapor space downwardly and ultimately discharging it into said lower analyzer vapor inlet against the pressure head existing at said inlet.

8.` The assembly of claim l wherein: the analyzer low level is located at an elevation not higher than the separator level nor lower than the top side of the connection between the vapor pressure tube and the generator vapor space.

9. A generator for absorption systems for distilling a refrigerant vapor and providing circulation of liquor from the low circuit low liquid level in the generator assembly to the high circuit delivery level in the upper portion of the absorber, comprising: a boiler with a heating tube passing therethrough and partitioned at the cooler end of the boiler into a lower high circuit chamber which extends toward the hot end of the boiler and an upper low circuit chamber; a vapor lift, including a vapor-collecting dome submerged below the` level of the low circuit charnber, for pumping liquor from the low circuit chamber upwardly by vapor generated in the high circuit chamber and collected in the dome of the vapor lift; a separator and pressure chamber submerged in the liquid of the low circuit chamber for separating the vapor and liquid delivered thereto by the vapor pump and having a tube to discharge the vapor into the cooler rich liquor of the low circuit chamber, at a substantially lower level than the separator, to pass therethrough for rectification and cooling and for directing the separated liquor into the high circuit chamber through which it is forced by the pressure de.- veloped in said separator chamber; and a passageway leading from the hot end of the boiler for taking the weak liquid and elevating it to the upper portion of the absorber due to the diierence in liquid levels arising from the pressure accumulating in the separator chamber and then made effective` against the liquid in the high circuit chamber. i 1G. The combination claimed in claim 9 in which the vapor-collecting dome of the vapor lift is located at the partition between the high and the low circuit chambers.

11. The combination claimed in claim 9 in which the vapor-collecting dome of the vapor lift is located at the partition between the high and the low circuit chambers and at a high point in the high circuit chamber and is provided with a downgoing vapor feed tube which leads to the vapor orifice at the lower end oi the vapor lift tube .passing into the separator.

l2. The combination claimed in claim 9, in which the vapor-collecting dome of the vapor lift is located at the partition between the high and the low circuit chambers and at a high point in said high circuit chamber and is provided with a downgoing vapor feed tube which leads to the vapor orifice at the lower end of the vapor lift tube passing into the separator, which separator is located in the low circuit chamber above the high circuit chamber. l

13. The combination claimed in claim 9 in which the vapor-collecting dome of the vapor lift is located at the partition between the high and the low circuit chambers and at a high point in the high circuit chamber and is provided with a downgoing vapor feed tube which leads to the vapor orifice at the lower end of the vapor lift tube passing into the separator, which separator is located in the low circuit chamber above the high circuit chamber, the said separator being provided with a downwardly directed vapor discharge tube for discharging the separated vapor at a lower point in the low circuit chamber of the generator to permit the vapor to rise in said chamber in countercurrent to the incoming cool rich liquor from the absorber and to form a vapor piston to transmit the gravity pressure of the liquid column in the upper low circuit chamber t0 the iluid in the separator.

14. The combination claimed in claim 9 to which is added a weak liquor jacket secured around the boiler and having a passage connected with the hot end of the boiler for delivery of the weak liquor from the hot end of the boiler through the jacket to a discharge tube leading to the absorber.

l5. The combination claimed in claim 9 to which is added a weak liquor jacket secured around the boiler and having a passage connected with the hot end of the boiler for delivery of the weak liquor from the hot end of the boiler through the jacket to a discharge tube leading to the absorber, the said jacket having a vent tube leading up above the lower liquid level of the boiler to the vapor discharge space.

16. The combination claimed in claim 9 in which the boiler has an upstanding portion and at its lower end a lateral extension with an elbow-like heater tube passing through the lateral extension and the upstanding portion of the boiler.

17. The combination claimed in claim 9 in which the boiler has an upstanding portion and at its lower end a lateral extension with an elbow-like heater tube passing through the lateral extension and the upstanding portion of the boiler, and in which a partition in the upstanding portion provides an upgoing leg for the lower high circuit chamber and a downgoing leg for the upper low circuit chamber.

18. The combination claimed in claim 9 in which the boiler has an upstanding portion and at its lower end a lateral extension with an elbow-like heater tube passing through the lateral extension and the upstanding portion of the,

from said domem the Ounce in. the vapor lift tube, the vaporlift tube and the two downgoing legs all being located in a downgoing leg of the upper low circuit chamber of the boiler, said vapor separa-tor having a downgoing liquid discharge leg passing through the upgoing leg of the lower high lcircuit chamber for discharging liquid from the separator chamber into said high circuit chamber under pressure.

19. A generator for absorption systems forfdistilling a refrigerant vapor and providing circulation of liquor from the low circuit low liquid level in the generator assembly to the high circuit delivery level in the upper portion of the absorber, comprising: a boiler with a heating tube. passing therethrough and partitioned at the cooler` end of the boiler into a high circuit chamberl which extends towards the hot end of theboiler and a low circuit chamber; a vapor lift wholly submerged inY the low circuit chamber for pumping liquor from the low circuit chamber upwardly by vapor generated in the high circuit chamber and collected in the dome of the vapor lift; a separator and pressure chamber wholly submerged in ther low circuit chamber for separating the vapor and liquid delivered thereto by thevapor pump and directing the vapor into the cool rich liquor of the low circuit chamber to pass therethrough for rectification and cooling and for directing the separated liquor into the highY circuit chamber through which it is forced bythe pressure developed in said separator chamber; and a passageway leading from the hot end of the boiler for taking the weak liquor and elevating it to the upper-portion of the absorber due to the difference in liquid levels in the high and low liquid level chambers arising from the pressure accumulating in the separator chamber and made effective against the liquid in the high circuit chamber; the said boiler having an upstanding portion and a partition dividing the boiler into an upper low circuit chamber having a depending leg and a lower high circuit chamber having an upgoing leg.

20. A generator for absorption systems for distilling a refrigerant vapor and providing circulation of liquor from the low circuit low liquid level in the generator assembly to the high circuit delivery level in the upper portion of the absorber, comprising: a boiler with a heating tube passing therethrough and partitioned at the cooler end of the boiler into a high circuit chamber which extends toward the hot end of the boiler and a low circuit chamber; a vapor lift wholly submerged in the low circuit chamber for pumping liquor from the low circuit chamber upwardly byA vapor generated in the high circuit chamber and collected in the dome of the vapor lift; a separator and pressure chamber whollysubmerged in the liquid of the low circuitchamber for separating the vapor and liquid delivered thereto by the vapor pump and directing the Vapor into the cool rich liquor of the low circuit; chamber to pass therethrough for rectification and cooling and for directing the separated liquor into the high circuit chamber through which it is forced byl the pressure developed in said separator chamber; and a passageway leading from the hot-end of the boiler for taking the weak liquor and elevating it to the upper portion of the absorber due to the difference in liquid levels in the high and low circuit chambers arising from the pressure accumulating in the separator chamber and made effective againstthe liquid in the high, circuit chamber; the said boiler having an upstandin'g portion and a partition dividing the boiler into an upper low circuit chamber having a depending leg and av lower high circuit chamber having. an upgoing leg; the vapor-collecting dome of the vapor lift being located at the top of an upgoing leg of the lower high circuit chamber and having a depending vapor feed tube for taking the vapor from the dome down tothe inlet orifice of the vapor lift tube, which vapor lift tube is located in thedowngoing leg of the upper circuit chamber; and the said vapor separator being located in the upper portion of said low circuit chamber and having a downgoing vapor discharge tube or leg located in a downgoing leg of said low circuit chamber.

2li. ln an absorption refrigeration system: an absorber; a generator; conduits connecting the sameA for circulating the rich liquor from the absorber through a low circuit to the generator by gravity and the weak liquor from the generator through a -high circuit to the absorber at an elevated point in the absorber; the said generator being compartmented to provide an upper low circuit chamber and a lower high circuit chamber; a separator extending above the liquid level of said high circuit chamber-g and a vapor lift pump for lifting low level liquid into said separator, said pump including a lift tube in the upper low circuit chamber and a dome roviding a lifting-vapor-collectingspace located in the lower high circuit chamber over the liquid level thereof; the said separator having a vapor discharge tube extending downwardly in the upper low circuit chamber thereby causing the hydraulic column in said upper low circuit chamber to have its pressure head, at the lower end of said vapor discharge tube, lifted to a higher point by the vapor in said discharge tube for application through the iluid in the separator to the hydraulic column in said lower high circuit chamber whereby to establish a higher head for the liquid of said lower high circuit chamber for the purpose of causing the weak liquor to pass through the high circuit conduits to the upper portion of the absorber.

22. In an absorption refrigeration system: an absorber; a generator; conduits connecting the same for circulating the rich liquor from the absorber through a low circuit to the generator by gravity and the weak liquor from the generator through a high circuit to the absorber at an elevated point in the absorber; the said generator being compartmented tof provide an upper low circuit chamber and a lower high` circuit chamber; a separator extending above the liquid level of said high circuit chamber; avapor lift pump for lifting low level liquid into said separator, said pump including a lift tube inthe upper low circuit chamber, a dome` providing a lifting-vapor-collecting space located in the lower high circuit chamber over the liquid level thereof and` a vapor discharge tube extending downwardly from said dome into said lifting tube; the said vapor-collectingk dome and vapor discharge tube thereby causing the hydraulic column in the upper chamber to have its pressure head, at the lower end of said discharge tube, lifted to a higher point by the vapor in said discharge tubefor application through theiiuid in the dome to the hydraulic column in said lower high circuit chamber` whereby to establish a higher head for the liquid of said lower high circuit chamber for the purpose of causing the weak liquor to pass through the` high circuit conduits to the upper portion of the absorber.

23. In an absorption refrigeration system: an absorber; a generator; conduits connecting the same for circulating the rich liquor from the absorber through a low circuit to the generator by gravity and the weak liquor from the generator through a high circuit to the absorber at an elevated point in the absorber; the said generator being compartmented to provide an upper low circuit chamber and a lower high circuit chamber; a separator extending above the liquid level of said high circuit chamber; a vapor lift pump for lifting low level liquid into said separator, said pump including a lifting tube in the upper low circuit chamber with a dome providing a lifting-vapor-collecting space located in the lower high circuit chamber over the liquid level thereof; the said vapor-collecting dome and separator having vapor discharge tubes extending downwardly in the upper chamber and discharging thereinto against the pressure head thereof thereby causing the hydraulic column in REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,664,471 Von Platen et al. Apr. 5, 1928 1,791,441 Bertsch Feb. 3, 1931 2,020,654 Nelson et al Nov. l2, 1935 2,080,195 Bergholm May 11, 1937 2,215,674 Ullstrand Sept. 24, 1940 2,337,653 Ehnbom Dec. 28, 1943 

